In analog synthesizers, the resonant filter uses a current limiting function,
preventing the signal from being too loud (soft clipping).
more natural. It also allows filters to enter self-oscillation like original
hardware synthesizers do.
Also, soft clipping can be a kind of saturation effect, but with a very
particular shape. Common shapes can't give good results compared to analog soft
clipping which is very particular to output amplification stages of analog
synthetisers, and is a critical component to "the analog sound".